Schema:
Physician (EmployeeID, Name, Position, SSN)
Department (DepartmentID, Name, Head)
Affiliated_With (Physician, Department, PrimaryAffiliation)
Procedures (Code, Name, Cost)
Trained_In (Physician, Treatment, CertificationDate, CertificationExpires)
Patient (SSN, Name, Address, Phone, InsuranceID, PCP)
Nurse (EmployeeID, Name, Position, Registered, SSN)
Appointment (AppointmentID, Patient, PrepNurse, Physician, Start, End, ExaminationRoom)
Medication (Code, Name, Brand, Description)
Prescribes (Physician, Patient, Medication, Date, Appointment, Dose)
Block (BlockFloor, BlockCode)
Room (RoomNumber, RoomType, BlockFloor, BlockCode, Unavailable)
On_Call (Nurse, BlockFloor, BlockCode, OnCallStart, OnCallEnd)
Stay (StayID, Patient, Room, StayStart, StayEnd)
Undergoes (Patient, Procedures, Stay, DateUndergoes, Physician, AssistingNurse)
Please answer with SQL.